Cushioning means for power presses



J. NELSON CUSHIONING YMEANS FOR *POWER PRESSES pFiied June 14. 1925 4 sheets-Sheet 2 Junle 21, 1927. v

June 21 1927 .1. NELSON CUSHIONING MEANS FOR POWER PRESSES 4 Sheets-Sheet 3 Filed June 14, 1925' June 21, 1927;

- A J. NELSON CUSHIONING MEANS FOR POWER FRESSES r 4 Sheets-Sheet 4 Filed June 14. 1925 f A f l m w i ./MWMLL u W/ ./mwm www. ,@m@

Patented June 21, 1927.

stares PATENT 'OFF'ICE.

JOHN NELSON, OF CHICGO, ILLINOIS.

CUSHIONING MEANS non POWER. PRE'ssEs.

Application filed .Tune 1'4, 1926. s'e'r'iai Nb; iisg'zs. This invention relates to cushioning means mental sectional View of the power press 50 for power presses. ai'id its piiiicipalfobiect showing the drawing, cusl'iio-mng means and is to provide cushioni'ng` means for the bolother associated parts in adilerent position ster or other die support, normally operating from tlia'tishovvn in Fig. IiFig. 3 is liori- 5 to support the bolster or die support in operz'ontal section-V taken on the line 3;'-3 of Fig. 2;

'ative position', but acting under tlie influence Fig. 4 isa view, partly inl endy eleva-tionE andl 55l of abnori'iial or excessive pressure or strains', partly in vertical section, the liner of sect-ion to yieldl and thereby prevent injury to the -be'iiigfindicated at 4% iii F ig. 1 and een press. Another object is to' provide bolster tain parts beiiig broken out-to illustrate parts 10 supporting means, movable under the ap-A th'at would otherwise be hidfdei'iA from viei'v;

plicatioii of abnormal or excessive pressure Fig. 5' a view looking from' bel'ovv" of 60 on the bolster and' having means for indicatcertain pressure cylinders and showing the' ingvthe amount of pressure exerted against arrangement of piping connections i'vitli the bolster, vand in this' manner ni'alre it posthem; F ig; 6` is a detail ho'riioiitalj section i sible for anl attendant to determine' tbe taken on'tli'e line 5 6 of F l and F ig.I 7

amount of pressure required for any given is an enlargeddetail vertical section' taken 65 ivorli and to ascertainJ the strain which a on the line 7`7'of F i'gs. 3 anld 6. given press structure will stand. Another Referring to said drawings, which illus-l object is to provide pressure means for yieldtrate one embodiment lof the present inven 'i'' ingl'y supporting,` the' drawV ring of presses tion, t-he reference character 150 designates that employ a draw ringP in the format-ion the; bodyvr o'r frame of a power die `press' of 701 olE certain Work, said pressure means forni` Ordinary and Well knownr Construction of ing` a part of and operating iii connection which llfd'esigiiates the base'or bed, and l2 with certain elements of the bolster cuslithe upright'rfraine i'ifilenibe'rs.l The press is' 25 ioi'iiiig' i'iieans` to support the bolster. shown as' mounted on piers or colun'ins 13 ot lWith .tl'i'ese and other ends in view, this the foundation 14 whichcontainstheusual pitv 75 invention consists' in al poive'r press' havingI below the press. The ram is designated by a' bolster or other die support, supported by Athejreference character lf 'and is guided upoir a mobile element, such as a fluid, under the uprights 12in they usual4 manner andis lll pressure. It further consists in a Huid presreciprocated by the cranks or other operatsure' supported bolster, having' associated iiig'mec'hanismof the press.v Thel bolster isv so i'vitli the receptacle for the fluid, a pressure shown at` 16 and itsupports the" female die' gauge whereby the amount of pressure en# 17. InA certain classes ofv Work', a" diraiv ring,`

erted upon the bolster may be ascertained. 18 is e'iiiployed,'vvhich is sh'ovvn4 as supported- It further consists in a power press having'. by yupright siipportingmei'iibers usually in i'uid pressure. cushioning means for the dravv the forni of rods" or bars 19, whichv rods or 85 ring, and mechanism co-operatingtherewith bars rest upon' and are supported by` a .pres-A to support. the bolster in position, but acting sure pad- 2O4 located b'elovv the' bolster. Tlief under the influence oi abnormal or excessive male di'es21, 22 aiemou'nted o'nfth'e ram' as 4U pressure, to permit the'bolster to yield. 'It usual and co-operate'ivith the feii'ialediestor further consists in the several novel features give shape tof theblanlr Wliicl'i is interposed'v 9o'A hereinafter fully set forth andiclaimed'. between the two sets off dies. In general the. The invention is clearly illustrated in the parts thus" far described are common and accompanying drawings, in which Wellkii'own and' require no detailed descrip'' 45 Fig. l is a view, partly in side elevation' tion so far' as the spe'ciic'ation is 'concerned and partly. iii vertical section, of a power The pressure pad' 20 is yi'el'di'iigly sup-l 95y press partly br'olten a'wvayaiid equipped with ported' by certain' elements' ot the pressure cushioning means embodying' a simple form members, which as here shoi'vn coi'irprise'y of the present invention; F i'g. 2 is a fragcon'ipres'sed air cylinclers 23;"an'd pist-ons 27.

As a preference the cylinders are provided with short stems or. necks 24 that project up through holes 25 formed in the pressure pad and under certain circumstances may serve to aid in supporting the bolster. The cylinders 28, may bear .directly against the pressure pad if desired, but for obtaining certain results l provide spacers or slotted collars 26 between the cylinders and pressure pad, which slotted collars are slipped upon the necks 24 and hold the ends of the necks 24 spaced away from the bolster 16. As above stated under certain circumstances certain of the slit collars may be removed thereby permitting the cylinders to engage the bolster directly through the interposed necks 24.

Within the cylinders 28 are pistons 27, which are mounted upon stems 28 here shown as supported by a floating platform 29. rlhe stems 28 are shown as formed with enlargements or heads 3() that bear against the top of the floating platform 29, and below the heads, the stems are threaded and extend through holes in the floating platform and have nuts 81 threaded thereon for rigidly connecting the piston stems` with said plat form. 1n the form of the invention illustrated, the stems 28 are hollow and each has a compressed air pipe 82 threadedly secured in its lower end and connected to compressed air tanks 38, 34, by flexible connections 36, 86=L and 861 and pipes 37, 87 and 87h. Any desirable number of com^ pressed air cylinders 28, may be employed and for the purposes of illustration, 1 have shown six of them arranged below the pressure pad and arranged in pairs, those olf each pair being connected to one of the compressed air tanks and those of each other pair being connected to a separate compressed air tank. This arrangement permits greater pressure to be applied to the pressure pad at certain places than at others, which may be required under certain working conditions.

In the apparatus thus far described, whenever the draw ring 18 is moved downward, the supporting rods 19 are moved downward by the draw ring, the pressure pad 2O is moved downward and therewith the compressed air cylinders 23, which are moved downward against the pressure between the heads of the cylinders and pistons 27. The necessary pressure is thus maintained to cause the draw ring to function properly.

Occasionally two blanks are accidentally placed between the dies, or some other foreign object finds its way between the dies, with the result that when the ram comes down to perform its work, the foreign intervening matter Causes abnormal strains and stresses on the crank shaft, its bearings, the frame and other parts and frequently causing permanent injury to the press. Ac-

cording to the present invention the bolster 1G, instead of being stationary, is supported by the pressure members and certain mechanism connected therewith, and is yieldingly held upward against shoulders 88, which may be in the form of bars or keys let into the inner faces of the upright frame member 12. The mechanism for supporting the bolster in operative position will not be described.

Below the bolster are supports or posts 39 which project through openings in the pressure pad 2O and bear against the underside of the bolster. Mechanism is provided for applying force to said supports or posts 39 in an upward force to hold the bolster up in contact with the shoulders 88 against all normal working downward pressure on the bolster. 1n the form of mechanism illustrated for accomplishing this result the posts or uprights 39 are shown as formed with rack bars 40 which mesh with gear segments 41 that are mounted upon rock shafts 42 rotatively mounted in brackets 43 that are supported upon a stationary platform 44 which is shown as suspended from the base or bed 11 by bolts or rods and nuts 45. The gear segments are shown as comprising the short arms of levers 46, the long arms 4T of which, are connected to the floating platform 29 by links 48. For the purpose of obtaining more or less leverage the lever arms 47 have adjustable connections with the links, and as shown may be provided with a plurality of places for lconnection with ,the links 48. Guide rollers 50 are journaled upon the brackets 48 at places opposite the gear segments 41 and operate to hold the rack bars 4() in mesh with said gear segments. As a preference the posts or uprights 89 are ar ranged adjacent the corners of the bolster and as shown are arranged in pairs, the two at each end of the bolster comprising a pair, and the two gear segments which mesh with the rack bars of the pair are rigidly secured upon a rock shaft 42, common to both, whereby, in case excessive pressure is brought to bear upon any corner ofv the bolster and that corner is depressed, a downward movement of that corner of the bolster will be transmitted to the other corner through the instrumentality of the posts.v rack bars, gear segments and rock shaft.

1t will be observed that the pressure within the cylinders 28 tends to force the cylinders upward and the pistons downward. As consequence the floating platform 29 is pressed in av downward direction and the long arms 47 of the levers 46 are thereby forced in a downward direction, thereby forcing the short arms or gear segments 41 of the levers 46 in an upward direction and therewith 'forcing upward the rack bars 4U and posts or uprights 89, which because of direction and with suicient Uil lill) their engagement with the underside of the bolster, '16 force it upward against the shoulders 3S. inasmuch as the pressure within the cylinders 23, is calculated to properly cushion the draw ring and is not suiicient ot itselir to properly support the bolster, the long arms i7 of the levers 46 are made several times the length of the short arms oi said levers in order to obtain suliicient leverage'to provide the necessary force to properly support the bolster during allnornnil working conditions. p

inasmuch as it sometimes occurs that an abnormal pressureis applied to one end only of the bolster, and as it is important that the bolster yield evenly at all places, I have provided parallel movement "mechanism be-v tween the iioatingplattorm 29 and stationary platform 44C which may comprise bars 50, l pivotally connected between their ends by links 52, and pivotally connected atV these ends with the two platforms. There are two parallel bars which are rigidly connected together by a cross bar 53 and' two bars 5l rigidly connectedby cross bars 54. One end of each bar is pivotally connected to the floating platform and the other endto the stationary platform. The parallel movement mechanism described is common and well known and is chosen for the purposes oit' illustration only.' Its function is to give a parallel 'movement` to the floating platform in case excessive pressure is applied to one end only of its bolster.

is has been previously described the severalr pairs oic'fiuid pressure cylinders, are respectively connected to compressed air tanks 33, 34:, 85. Compressed air issupplied to said tanks from a suitable source, and it' desired each tank may be equipped with a. pressure gauge 55 and a pressure regulating valve 5G, which instruments may be placed:

on the compressed air pipes 57 which lead'to the several tanks. t desired the main coinpressed air pipe 58, which leads from the l compressor or other source of'compressed fluid, may have a pressure regulating` valve 59 therein and the pipes 57 may be coupledto the main pipe '58 at a point between the pressure regulating` valve 59 and the tanks.

in connection with the pressure gauges, chart or charts may be employed which may be calibrated to show 'the tonnage indicated by the pressure gauges, namely the tonnage'which the bolster will support without` yielding. i

In the operationof the cusliioningnieans illustrated, the proper pressure. being supplied tothe compressed air tanks, the compressed air enters the pressure cylinders 23, and toi-ces the pistons 27' downward and the cylinders 23 upward, thereby depressing i the floating platform 29, swinging down Vthe long arms 4i? of the levers 46,' andl moving the gear segments 4l upward, which in turn vlustratedvv in dotted lines in Fig.

lift the yrack bars'fiO and posts or uprights 3S), thereby moving the bolster, aiidparts ried thereby upward unt-il the bolster encounters the Shoulders 38, where it is held until depressed by the application of abnormal downward pressure thereon. rlihe upward pressure of the iiuid on the cylinders,

raises them and therewith the pressure pad and drawring, bringing the pressure pad into Contact with the lower side ot' tlie'bolster. This is the position of the parts when the ypress is at rest.

is started and the raml is brought down, the male dies engaging the blank and perform,-

ing whatever work is to be done. In certain.

kinds of work the pressure cylinders, inerely holdl the draw ring up against the blank vith sufiicicnt torce to permit the male' die to perform its work properly. In certain other operations the draw ring is movedf Athe pressure pad 20 has been moved down by the rods 19, which support the draw ring, and tlie cylinders 23, have been moved: downward against the pressure within them. fvvhen the ram starts on its up stroke andthe A blank being placed. on the l'emale die and draw ring, the press down pressure on tlie draw ring is released,y

the cylinders 23, pressure pad 20, rods vi9 and draw ring are forced upward by the compressed air. f

In case an abnormal or excessive pressure is pl ced upon `the bolster, as ior instance two blanks are accidentally placed between the diesandthe yrain is brought down, instead or" placing an abnormal strain on the press, springing the crank shatter breaking some part or the press, the bolster is depressed against the action or the cushioning Such a position of the parts is il'- 7 where the pressure pad is shown normally depress l in full i-ines due to the ordinary action oit the draw ringl position, by thedotted lines. It will'be observedthat when the bolster is depressed, the long arm l''ot the lever 4 6 is swung upward, thereby raising the floating platform 29 and therewith the pistons-27 against the pressure in the cylinders 23. As soon as thev abnormal pressure on the bolster is removed the pistons 2T are depressed and the bolster restored to normal poitionthro-ugh the instrumentality of the floating platform levers i6 and posts 39.

It will be understood that by setting the respective pressure regulating valves, 56, the pressure vin any pair ofcylinders 23 may be varied to suit any, peculiar requirement.

The bolster is shown in nor-y nial position in full lines and in depressed Furthermore that with the use ot the pressure regulating valve 59 on the main compressed air pipe 57, the valves 56, may be neutralized and an equal pressure may be had in all ot the tanks and all of the pressure cylinders 23, thereby distributing the pressure equally on the pressure pad and on the bolster.

Under certain conditions it may be found advantageous to supply greater' upward pressure on the bolster and less upward pressure on the draw ring. Any ot the split collars 26 may be removed from its cylinder 23, thereby permitting the neck 2e o'i the cylinder to engage with the under side ot its bolster thusl applying the pressure of that cylinder' to the bolster, and relieving the pressure pad oi the pressure. This may be done at any desired places whereby additional pressure may be supplied to the bolster at the desired place and the pressure correspondingly removed from the pressure pad.

I claim as new, and desire to secure by Letters Patent:

l. ln a power press, the combination with the bolster and ram members et a presi, o't means to resist breaking down ot the press under abnormal pressure between the bolster and ram members and comprising l'iuid pressure operated (cfushioningl means haring one element tliereoi connected to one of said memi bers and acting to unyieldingly hold said member in tixed position against a maximum predetermined pressure between said members, but capable ot yielding when said member is subjected to an abnormal pressure by the other member in excess of said maximum predetermined pressure.

2. ln a pow n' press, the combination with a normally unyielding bolster and the ram ot a press, of means to resist breaking down ot' the press under abnormal pressure between said bolster and ram and comprising liuid pressure operated bolster supporting means 'for unyieldingly holding said bolster in lixed position and against a. maximum predetermined pressure by the ram, but capable oi yielding when said bolster is subjected to an abnormal pressure by the ram in excess ot said maximum predetern'iined'pressure.

3. In a power press, th combination with a normally unyielding bolster and the ram of a press, of means to resist brea ing down ot the press under abnormal pressure between said bolster and ram and comprising pressure operated cushioning means, bolster supporting elements actuated thereby and connected to said bolster and unyieldingly supporting the same in iixed `position against a maximum predetermined pressure, but capable of yielding .under the influence of an abnormal pressure by said ram in excess of said predetermined maximum pressure;

li. In a power press, the combination with a normally unyielding bolster and the ram oi' a press, of means to resist breaking down oi' the press under abnormal pressure between said bolster and ram and comprising luid pressure operated bolster supporting means for unyieldingly supporting the bolster in fixed position against a predetermined maximum pressure, but capable orn yielding under the influence ot an abnormal pressure in excess of said predetermined maximum pressure, said pressure operated means having a pressure gauge associated therewith and indicating the pressure applied to the bolster.

5. in a power press, the combination with a normally unyielding bolster and the ram of a press, of bolster supporting mechanism for normally unyieldingly holding said bolster in iixed position and including force multiplying levers, fluid pressure cushioning members and operative connections between said fluid pressure cushioning members and torce multiplying levers, said fluid pressure cushioning members acting to permit the bolster to yield under the influence ot abnormal pressurel thereon by the ram in Yexcess ot a maximum predetermined pressure.

(i. ln a power press, the combination with a normally unyielding bolster and the ram off a press, ot bolster supporting uprights, torce multiplyinglevers supportingly engagging said uprights, lmd pressure cushioning members, operative connections between said Vl'luid pressure cushioning member and force nniiltiplying` levers and an abutment member for saidbolster, said fluid pressure cushioning members operating to unyieldingly hold said bolster up in iixed position` against said abutment member against a maximum predetermined downward 'pressure thereon.

7. ln a power press, the combination with the ram, bolster and pressure pad of a press, oi combined bolster and pressure pad supporting members, comprising,levers operatively eonnected to the bolster, and liuid pressure members having elements engaging the pressure pad and other elements operatively eonnect-ed to said levers. and an abutment for said bolster, said liuid pressure members operating to yieldin'gly supportthe pressure pad against a predetermined downward pressure, and operating to support the bolster against a higher predetermined downward pressure.

8. In a power press, the combination with the ram, bolster and pressure pad olf a press, of combined bolster and pressure pad supporting members, comprising` upright bolster supports, levers supportingly engaging said supports, and fluid pressure members having elements engaging the pressure pad and other elements operatively connected to said levers, and an abutment for said bol- Slo les

ster, said pressure members operating to yieldingly support the pressure pad'against. a predetermined(downward pressure, and operating to supportv the bolster against a, higher predetermined downward pressure.

9. In a power press, the combination with the rain, bolster and pressure pad of a press, of combined'bolster ancL pressure pad supporting members, comprising upright bolster supports, rack bars thereon, levers having gear segments meshing with said racks, fluid pressure members having eleinents'supportingly engagingsaid levers, and an abutment for said bolster, said fluid pressure members operating to yieldingly support said pressure pad against a predetermined pressure, and operating to support said bolster against a higher predetermined downward pressure.

10. In a power press` the combination with the ram, bolster and pressure pad of a press, of combined bolster and pressure pad supporting members, comprising upright bolster supports, levers supportinejly engaging said supports, fluid presure cylinders supportingly engaging said pressure pad, pistons in said cylinders and stems for said pistons, a floating platform secured to said piston stems and operatively connected to said levers, an abutment for said bolster, and means for supplying fluid under pressure to said cylinders.

11. In a power press, the combination with the ram. bolster and pressure pad of a press, of combined bolster and pressure pad supporting members, comprising upright bolster supports, rack bars on said supports, levers having gear segments thereon meshing with said rack bars, fluid pressure cylinders supportingly engaging said pressure pad, pistons in said cylinders and stems for said pistons, a floating platform secured to said piston stems and operatively connected to said levers, an abutment for said bolster, and means for supplying fluid under prese sure to sain cylinders.

12. In a power press, the combination with the ram.` bolster and pressure pad of a press, of combined bolster and pressure pad supporting members. comprising sta' tionarily supported brackets, levers Jfulcrumed on said brackets and supportingly engaging said supports, a floating platform to which said levers are operatively connected, fluid pressure members, having elements yieldingly supporting said pressure pad and other elements secured to said platform, and an abutment member for said bolster, said pressure members operating to yieldingly support said pressure pad against a predetermined downward pressure and operating to support said bolster' against a higher predetermined downward pressure.

3. In a power press, the combination -with bolster and pressure padof press,

the r 'i of combined bolster and pressure pad supporting means, comprising fluid; pressure cylinders and pistons therein,power'multif plying connections betweenthe pistons and bolster, constructed. and. arranged' to Supf port said.' bolster'` againstv awpredetermined downward press-ure thereon, said cylinders being: norii'ially'arranged to yieldinglyA support said pressure pad against a predetermined downward pressure, and having means arranged to transfer pressure from the pressure pad to the bolster, and means for supplying fluid under pressure to said pressure cylinders.

14. In a power press, the combination of the ram, bolster and pressure pad of a press, of cushioning means for the bolster and pressure pad, comprising fluid pressure members, each having two movable elements, one element thereof being provided with means for engagement with the pressure pad and the other element being provided with power multiplying means connected with the bolster for permitting the bolster to yield under abnormal pressure.

15. In a power press, the combination with the ram, bolster and pressure pad of a press, of' fluid pressure operated cushioning means for the bolster and pressure pad, comprising fluid pressure members having power multiplying connections with the bolster and direct connections with the pressure pad for permitting the bolster to yield under abnormal pressure, and means for supplying fluid under pressure to said pressure members.

16. In a power press, the combination with the ram, bolster and pressure pad of a press, of fluid pressure operated cushioning means for the bolster and pressure pad, comprising fluid pressure members, having power multiplying connections with the bolster, and operative connections with the pressure pad for permitting the bolster to yield under abnormal pressure and means for separately supplying the individual pressure members with fluid under pressure.

17. In a power `press,.the combination with the ram, bolster and pressure pad of' a press, offluid pressure operated cushioning means for the bolster and pressure pad, comprising pressure members, arranged in groups and having power multiplying connections with the bolster and operative connections with the pressure pad for permitting the bolster to yield underabnormal pressure and means for separately supplying the groups of pressure members with fluid under pressure.

18. In a power press, the combination with a normally unyielding bolster and the ram of a press, of fluid pressure operated cushioning means for unyieldingly holding the bolster in liXed operative position against a maximum predetermined 4pressure and perd mitting it to' yield under abnormal pressure and parallel mechanism connected Ulli to said bolster' and operating;` to guide movemaximum predeternned pressure and p rment thereof in parallel lines. initting' it to yield under abnormal pressure,

19. In a power press, the combination with and guiding means associated with said bol- 10 a normally unyielding bolster and the ram of ster operating to guide the saine to move in ='3 a press, of Huid pressure operated eusliionparallel lines.

ing means for unyieldingly holdingsaid loolster n fixed operative position against a l JOHN NELSON. 

